Distinguishing features: Test in a low to flat trochospiral coil, spiral side flat, umbilical side convex with wide umbilicus that is occupied by portici and tegilla, early chambers globular, later ones rhomboidal in section, sutures strongly curved, elevated and oblique on the spiral side, radial and depressed on the umbilical side, distinct peripheral keel on the edge of the spiral side, the umbilical peripheral margin with a less developed second keel consisting only of a row of pustules or this may be absent, peripheral outline entire to weakly lobulate; wall calcareous, perforate, surface pustulose, particularly on the umbilical side of the test; primary aperture interiomarginal, umbilical, and bordered by a wide porticus, those of successive chambers remaining as accessory apertures, and portici may fuse into tegilla in the later stage.

Geological Range: Last occurrence (top): within Maastrichtian Stage (66.04-72.05Ma, top in Maastrichtian stage). Data source: Total of range of species in this databaseFirst occurrence (base): within Santonian Stage (83.64-86.26Ma, base in Santonian stage). Data source: Total of range of species in this database

Plot of occurrence data:

Dec 2017 - Plotting of Neptune data has been re-enabled on the Mesozoic pages following revision of the age-models in Neptune. The data is, however, still very sparse for the Early Cretaceous